Question

A measure of physiological maturity in sugarcane is :

• A. Crop height
• B. Brix value
• C. Cane girth
• D. Leaf yellowing

Hint:

Brix Value $\rightarrow$ Sugarcane (Sugar content).
Oil content $\rightarrow$ Oilseeds.
Starch content $\rightarrow$ Potato/Tubers.
For sugarcane, the top-to-bottom Brix ratio (Brix index) should be close to 1.0 for perfect maturity.

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
Sugarcane is harvested for its sugar content. Identifying the point of maximum sugar accumulation is critical. The question asks for the technical measure used to determine if the cane is physiologically mature.
Detailed Explanation:

• Physiological Maturity vs. Physical Growth:
Crop height and cane girth are measures of vegetative growth, not necessarily maturity. A tall cane might still be watery and low in sugar.

• Brix Value (Degree Brix):
Brix value is a measure of the Total Soluble Solids (TSS) in a liquid. In sugarcane juice, about 80-90% of the TSS is sucrose.
A hand-held or digital refractometer is used in the field to check the Brix value of the juice.
Sugarcane is considered mature when the Brix value is uniform throughout the cane (top and bottom) and usually reaches around 18-20% or higher. At this point, the conversion of glucose/fructose into sucrose is maximal.

• Analyzing other options:
Leaf yellowing: Can be a sign of senescence or disease, but it's not a precise measure of sugar maturity.

Step 2: Final Answer:
The Brix value is the most reliable and common measure of physiological and commercial maturity in sugarcane.